Zhang Changhua and his wife, Chen Suqin, hail from a small farming village in Sichuan province. Some 15 years ago, they moved more than 1,000 miles away to densely populated, highly industrialized Guangdong (the province facing Hong Kong) to work in clothing factories, often making jeans for Westerners.

The price they paid was leaving behind their young children, daughter Qin and son Yang, to be raised by the kids' grandparents. The only time Changhua and Suqin can see them is during the Chinese New Year national holiday. The couple's arduous journey, via train, boat and bus, is part of a mass migration that takes place every year and involves, according to the pic, 130 million Chinese citizens.

Cleaving to a noninterventionist verite style that eschews voiceover and using all but minimal onscreen info, helmer Fan follows the couple over two years, starting with their annual cross-country journey in 2007. After braving enormous lines to secure cheaper return tickets, they battle huge crowds to get seats on the train for the long journey ahead.

The welcome, once they get home, is hardly warm. After years of separation, 16-year-old Qin and younger Yang barely know their parents. Outside the holiday visits, their contact with Mom and Dad has been largely confined to phone calls, during which Suqin mostly nags them to study harder.

Fed up with life in the sticks, Qin decides to come down Guangdong herself to get a job in a factory in Shenzhen, much to her parents' chagrin. The long hours and dormitory accommodations aren't a lot of fun, but for her, "freedom is happiness," especially if it means a chance to shop for her own clothes and go to nightclubs.

Long-buried resentments finally erupt during a New Year's visit in 2008, creating a possibly permanent breach.

Editing by Fan and Mary Stephen strives to provide a balance between the generations, leaving the impression that blame lies on both sides for the emotional estrangement. The real culprit is economic hardship in general, although broader perspectives are strictly visual here, confined to impressive wide-angle shots of crowds and landscapes.

Camera (color, HD), Fan; editors, Fan, Mary Stephen; sound, Fan, Cory Rizos. Reviewed online, Hoveton, U.K., Nov. 29, 2009. (In Intl. Documentary Festival Amsterdam, competing; also in Sundance Film Festival, World Cinema Documentary competition.) Running time: 87 MIN.